Our master bedroom is considerably warmer than the living/dining/kitchen area of our house, and we've been setting the thermostat quite lower than we'd like in order for the bedroom to get cool enough at night to sleep in. Upon exiting the bedroom in the morning, we've practically got to bundle up due to how cold the rest of the house is.

One suggestion we got was to install a return vent above the door, which we don't want to do because of the loss of privacy. Another suggestion was to install a jump duct in the ceiling inside and outside of the bedroom, which appeals to both my wife and me.

What is the correct way and what are the materials required to install a jump duct so as to maximize air circulation while not leaking any cold air into the attic?

2 Answers
2

Go to any big box store and get some 6" flexible insulated duct (this pic shows black sheathing on the outside, but it's often made of shiny reflective mylar):

And a couple of 6" boots, one for each end:

Use aluminum HVAC tape or a large band clamp or zip tie to connect the inner sleeve of the duct to the boots, then use another layer of tape to seal up the insulated layer and prevent it from sliding around. Cut holes in the ceiling to match the rectangular boot opening, keeping one long edge of each hole flush to a ceiling joist. Then take your duct assembly up into the attic and insert the boots into each hole. You can just leave the flexible duct lying on top of the ceiling joists. Back downstairs, use small nails (with heads, not finish nails) to nail through the inside of the boot opening into the side of the adjacent ceiling joist. Then install a couple of register grilles and you're done!

Bedroom is on the same level as the rest of the rooms. I don't understand the second part of your response... could you elaborate? We're actually in Florida and do not have a furnace... our concern is 100% cooling - don't care about heating at all.
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Michael MoussaAug 22 '10 at 18:27

A/C only will still give you problems. The attic is the hottest part of your house (same here in summer; coldest here in winter). If you run the ductwork up through the attic, it's going to get heated more than if it was going through the basement/crawlspace. Going through the attic is definitely easier though. If you do, bury the duct in tons of insulation- several feet would be best (blown-in cellulose is easiest). That flexible duct has very little insulation on it and will heat up considerably.
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nstenzAug 24 '10 at 20:27